{"schemaVersion":1,"slug":"67yn-multifrequency-admittance-earth-fault-protection","name":"Multifrequency admittance earth-fault protection","kind":"function","abbreviation":"67YN","aliases":["multifrequency earth fault","MFADPSDE","ANSI 67YN","IEEE 67YN"],"category":"measurement-protection","drawingTypes":["SLD","Schematic"],"referenceFamilies":["IEEE / ANSI","Manufacturer"],"summary":"Assesses earth-fault behaviour using the manufacturer's multifrequency admittance-based method.","description":["Assesses earth-fault behaviour using the manufacturer's multifrequency admittance-based method.","The drafting record should connect this function to the residual current and residual voltage channels and neutral-earthing reference, then trace the admittance earth-fault function and feeder tripping output. Keep the complete designation and equipment tag together so that the SLD, relay logic and terminal schedule describe the same implementation.","The cited mapping is a public manufacturer example (ABB Relion 620 function mapping). Suffixes are not universal equivalences across products, and this reference supplies neither a protection setting nor certification of the selected scheme."],"readingNotes":["Identify the residual current and residual voltage channels and neutral-earthing reference.","Trace the admittance earth-fault function and feeder tripping output."],"drawingChecklist":["Label the residual current and residual voltage channels and neutral-earthing reference.","Cross-reference the admittance earth-fault function and feeder tripping output.","Retain the complete suffix, selected device tag and manufacturer manual revision."],"distinction":"ABB's 67YN mapping identifies a multifrequency method; it is not simply another pickup stage of 67N.","facts":[{"label":"Function designation","value":"67YN"},{"label":"Base function","value":"67 — Directional overcurrent"},{"label":"Published mapping","value":"ABB Relion 620 function mapping"},{"label":"Suffix scope","value":"Application or manufacturer specific; check the complete drawing legend and selected device manual."}],"references":[{"sourceId":"pub-function-abb-mappings","relevance":"Public primary-source function or application mapping used to identify this designation; wording and drafting notes are original."},{"sourceId":"ieee-functions","relevance":"Device-number and suffix convention. This page is not a reproduction of the full licensed standard."}],"related":["67-directional-overcurrent","current-transformer"],"artwork":"pub-function-box","publishedOn":"2026-10-13","updatedOn":"2026-10-13","provenance":"independent-public-research","url":"https://eloragrid.ai/protection-functions/67yn-multifrequency-admittance-earth-fault-protection","illustration":{"url":"https://eloragrid.ai/library/illustrations/67yn-multifrequency-admittance-earth-fault-protection.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pub-function-abb-mappings","title":"Relion 620 series: published protection function and designation mappings","publisher":"ABB","url":"https://techdoc.relays.protection-control.abb/r/620-series-IEC-60870-5-103-Point-List-Manual/2.0-FP1-IEC/en-US/Functions-codes-and-symbols","type":"manufacturer","scope":"Manufacturer mapping of function names, IEC identifiers and ANSI labels. These are examples for a documented product family, not universal equivalences between standards or products.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Public primary-source function or application mapping used to identify this designation; wording and drafting notes are original."},{"id":"ieee-functions","title":"IEEE C37.2-2022: power-system device function numbers","publisher":"IEEE","url":"https://ieeexplore.ieee.org/document/9984140","type":"standard","scope":"Device function numbers, acronyms and contact designations. The full publication may require access through IEEE.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Device-number and suffix convention. This page is not a reproduction of the full licensed standard."}]}